An ink jet recording method is capable of simply preparing an image at a low price, and thus, can be applied to various printing fields including special printing such as photographs, various printings, marking, and a color filter.
In an ink jet ink used for the ink jet recording method, there are a plurality of types of inks such as an aqueous ink containing water and a small amount of organic solvent, a non-aqueous ink containing an organic solvent but not substantially containing water, a hot-melt ink forming an image by heating and melting a solid ink at a room temperature, and an active light ray curable ink cured by being irradiated with an active light ray after being impacted onto a recording medium, and the ink jet inks are differently used according to the application.
Among them, in general, the aqueous ink is widely used for a household printer or the like from the viewpoint of less odor and high safety. In an ink jet image forming method using the aqueous ink, a water-absorption high recording medium is used, and thus, an excellent image quality is obtained. At this time, a technology is known in which a treatment liquid is applied in advance onto the recording medium, and thus, a quality of an image to be formed increases. For example, in the invention described in Patent Literature 1, an image is formed on regular paper onto which a treatment liquid containing a cation resin, an acid, and a surfactant is applied, by using an aqueous ink containing a coloring agent, a water soluble organic solvent, a surfactant, and a penetrating agent, and thus, a concentration of an image to be formed increases, and abrasion resistance of the image increases.
On the other hand, the aqueous ink has a low viscosity. For this reason, in a case where an image is formed with respect to a recording medium hardly absorbing water of coated paper for gravure or offset printing and a non-water-absorption recording medium such as a film (hereinafter, also simply referred to as a “low water-absorption recording medium”) by the aqueous ink, the ink is retained on the recording medium for a long period of time, and thus, blur due to wet spread of an ink droplet easily occurs on the image, or adhesiveness of the image with respect to the recording medium decreases. Regarding such problems, a technology is known in which the treatment liquid is applied in advance onto the recording medium, and thus, blur on the image is suppressed, and the adhesiveness of the image increases. For example, in the invention described in Patent Literature 2, an image is formed on coated paper or a composite resin film onto which a treatment liquid containing polyvinyl alcohol having a saponification degree of less than or equal to 95% is applied, by using an aqueous ink, and thus, color mixture on an image to be formed is suppressed, and abrasion resistance of the image increases.